<div class="form-area">
  <app-login *ngIf="pageType === 'login'"></app-login>
  <app-register *ngIf="pageType === 'register'"></app-register>
  <app-forget *ngIf="pageType === 'forget'"></app-forget>
</div>
<div class="lang-change">
  <span [className]="this.lang === 'zh-CN' ? 'active' : ''" (click)="changeLang('zh-CN')">中文</span>
  <nz-divider nzType="vertical"></nz-divider>
  <span [className]="this.lang === 'en' ? 'active' : ''" (click)="changeLang('en')">English</span>
</div>